The centre said that as of January 17, 227,213 people had been fully vaccinated, way off the targeted population of 1,869,279.
Officials told The National newspaper that health workers noted more people appeared to be coming forward to be vaccinated, especially in Port Moresby.
NCC incident manager Dr Malinda Susapu said there was still a high transmission of the Delta variant and the original Covid-19 strain in the country, urging more people to get vaccinated and observe the niupela pasin (or new normal).
Susapu said the turnaround time for results would depend on the number of samples the Doherty Institute in Melbourne, where genomic sequencing is done, received from Papua New Guinea and Australia.
"Previously, when Australia had a surge, it greatly impacted on the turnaround time for our results, which is between two and three weeks," she said.
Susapu told The National that because of low testing during the festive period, there was a low number of reported cases.
But she said this did not mean that there was a decrease in Covid-19 cases adding that many health workers took a break over the festive period, reducing the workforce at testing facilities.
Susapu said the scaling down of services in health facilities during the government shut-down period had also impacted swabbing and testing for the Covid-19.